scharff



Nov. 25, 1941. 'J. E. SCHARFF APPARATUS FOR CONDITIONING AIR 3 Shee ts- Sheef l Filed Dec. 16, 1958' (DOOCQ) 25, 1941? J. E. SCHARFF APPARATUS FOR CONDITIONING-AIR s Sheets-Sheet 2 Filed Dec. 16, 1958 N RN g Q A \NVE R in? M 7 ATTORNEYS.

N/ TNESS l Nov. 25, 1941.

J. E. SCHARFF APPARATUS FOR CONDITIONING- AIR Filed Dec. 16, 1958 3 Sheets-Sheet 5 E U A a L/OHN E.

lNVENT BY ATTORNEYS.

Patented Nov. 25, 1941 srrimn'rns roa CONDITIONING Am 3 Claims.

This invention relates to a new and improved apparatus for conditioning air and more particularly it pertains to an apparatus for delivering air at a predetermined temperature to a suitable air distributing system.

All methods and apparatus for obtaining the results of the present invention, with which I am familiar, have certain objectionable features and it is the primary object of the invention to provide an apparatus in which these objections are removed, thus greatly increasing the efliciency of such devices.

One undesirable feature prevalent in methods and apparatus of the afore-mentioned type is that they do not supply a continuous flow of air at the desired temperatures during their operating period, their operation being intermittent, even while building up to the desired temperature. This intermittent operating results primarily from the fact that the heat exchange units or elements employed in prior system fall rapidly from their points of maximum efiiciency to points where the desired temperatures of the air cannot be obtained. When such ineiilcient points are reached, the circulation of air in the presence of the heat exchange elements must necessarily be arrested or stopped until such time as the heat exchange elements can again be built up to an cificient point. Such a system requires a relatively larger consumption of fuel than does a system which operates continuously and further, is less efiicient in maintaining the desired temperatures at points desired.

A feature of the present invention resides in a novel construction and arrangement of parts whereby a constantly flowing or moving volume of air is continuously delivered at any desired temperature, during operation of the device.

A further feature of the invention resides in a novel construction whereby the so-called cold spot at the point of delivery of the aiir, which cold spot is so prevalent in prior devices, is eliminated.

Other features of the invention relate to certain novel and improved constructions, arrangements and combinations of parts hereinafter de- In the drawings:

Figure l is a view in elevation illustrating a device constructed in accordance with the present invention,

Figure 2 is a horizontal sectional view taken substantially on the line 2-2 of Figure 1,

Figure 3 is a detail sectional view taken substantially on the line 3-3 of Figure 2,

Figure 4 is a detail fragmentary sectional view taken substantially on the line 4-4 of Figure 1,

Figure 5 is a view in elevation of a heating device employed in connection with the present invention,

Figure 6 is a longitudinal sectional view on an enlarged scale of the heating device, taken substantially on the line 66 of Figure 5,

Figure '7 is a transverse sectional view taken Y substantially on the line ll of Figure 6, and

scribed and particularly pointed out in the I Figure 8 is a transverse sectional view taken substantially on the line 8-8 of Figure 6.

In ,the illustrated embodiment of the invention, the reference numeral iii designates a housing. This housing which forms an air chamber ii is of rectangular form and preferably substantially square in cross-section although, other forms of housings may be resorted to without departing from the spirit of the invention and it is to be understood that this housing is to be suitably insulated. The air chamber has an air inlet l2 at one end thereof and an air outlet l3 at its other end. Mounted within the housing. there is an air impelling means in the form of a fan or blower M, the discharge of which is in the form of a hood 15 which preferably encompasses the area of the outlet opening IS.

The air is drawn into the air chamber II by the fan or blower l4 and by the same means it is discharged through the hood I5 and the air outlet I3 of the air chamber H. In its passage through the inlet l2, the air passes through 2 suitable filter l6 by means of which foreign matter in suspension is separated therefrom. This filter may be retained in position by a hinged door or the like I6 and retained in position by guides ll.

The reference numeral l8 designates a heat exchange element which is located in the path of the air as it passes from the filter IE to the interior of the air chamber I I and at the outlet end of the air chamber ii, there is a second heat exchange element 20. These heat exchange elements are of the fluid type and in the present embodiment of the invention, they are illustrated as being supplied with a suitable heating medium in the form of hot water.

It is to be understood however, that in the illustrated embodiment .of the invention, it is employed as means for heating air to be supplied to heating systems of the hot air type, and further that the invention is not to be limited to air heating, but is equally adaptable to air cooling merely by the circulation of a cooling fluid instead of a heating fluid to the heat exchange elements.

Each of the heat exchange elements comprises a pair of spaced wells or headers, there being a lower well or header 24 and an upper well or. header 28 in each heat exchange element. However, the top well or header of the heat exchange element I8 is preferably larger than is the top well of the heat exchange element 28. The upper and lower headers of each heat exchange element are connected together by tubes 28 which have communication with the headers so that a free circulation of fluid through the headers and the tubes may be had. The tubes in each heat exchange element are arranged in spaced relation to each other to permit of the passage of air through the heat exchange elements both as it enters and as it is discharged from the air cham ber.

By reference to Figure 2, it will be noted that at each end or side of the heat exchange element I8, there is an isolated group of tubes which tubes are designated 38 in said figure. Referring to Figure 4 it will be noted that the tubes 38 are arranged directly behind a mask 32 preferably in the form of an angle plate or iron which is of the desired length. By this construction it will be apparent that air entering the inlet will, by reason of the masks 32, be prevented from directly attacking that portion of the tubes 38 behind the masks and thus the heat exchange action in these tubes will be less than in the remainder of the tubes of the heat exchange element.

Figure 4 also discloses a modification of the invention in which the mask 32 may be extended by means of a detachable plate or the like 34 and by which arrangement certain of the tubes 28 may be also masked for the purpose of retarding their heat exchange action. The purpose of this special construction and the advantages obtained therefrom will be hereinafter more specifically set forth.

By reference to Figures 1 and 2, it will be noted that the upper header of the heat exchange element I8 is connected with the upper header of the heat exchange element 28. This connection consists, in the present embodiment of the invention, of two heat exchange elements 48 and 42. These heat exchange elements 48 and 42 are preferably in the form of pipes 44 bearing radiating fins 45 and they serve a dual purpose as will now be described. First: they supply the fluid to the heat exchange element 28 from the heat exchange element I8; Second: being heat exchange elements in themselves, they influence the temperature within the air chamber I I.

I will now describe the circulating system by means of which hot water is supplied to the heat exchange elements in order that the air in its passage in the presence thereof, may be heated.

For this purpose reference will be had to Figures 1 and 2. In Figure 1, the reference numeral 58 designates a water supply line which is connected as at 52 to a line I8, which constitutes a water feed line, a pressure relief line and an expansion line, an expansion tank being illustrated and designated 88. The supply of water from the line I8 to a return line 53 may be controlled by a small valve 54. The return line 53 is connected by means of a coupling 55 to a suitable water heater 56 herein illustrated as of the gas type. The reference numeral 51 designates a pet cock by means of which the entire system may be drained.

Leading from the dome 58 of the water heater 56 there is a hot water supply or feed pipe 59 and this pipe is connected as at 68 to the upper header26 of the heat exchange element I8. By this means, water heated to the desired temperature by the water heater 56 is delivered to the upper header 26 of the heat exchange element I8 and when the tubes of this heat exchange element have been filled, the hot water is delivered into the heat exchange elements 48 and 42 which serve to convey it to the header 26 of the heat exchange element 28 and it is to insure suflicient supply of fluid to the upper header of the heat exchange element 28 without effecting eflicient operation of the heat exchange element I8, that the upper header 26 of the heat exchange element I8 is increased in volume. Leading from the lower header 24 of the heat exchange element 28, there is a line 62. This line 62 is connected to one leg of a Y-fitting 64 and leading from the other leg of the Y-fitting 64, there is a line 66 which is also connected to the lower header 24 of the heat exchange element I8. Leading from the Y-fltting 64, there is a line I8 which is connected to one leg of a Y-fitting l2 and leading from this Y-fitting I2, there is a line I4 which constitutes the supply or inlet for a slow speed pump I6. The pump I6, as illustrated in Figure 1, discharges directly into the return Lne 53 and the line I8, heretofore mentioned, is connected to the other leg of the Y- fitting 12.

From the foregoing, it will be apparent that heated water supplied by the heater 56 will pass through the line 59, the heat exchange element I8, heat exchange elements 48 and 42 to the heat exchange element 28, line 62 and return line 53 to the point 56 and this circulation is maintained constant by mean of the slow speed pump I6.

The reference numeral 82 designates an electric motor and this motor drives the shaft 84 of the fan I4 through the medium of a belt 86 and a pulley 88, the latter being mounted on the shaft 84. The shaft 84 also carries a pulley 98 and this pulley 98 drives a belt 82 which in turn drives a pulley 94 carried upon the shaft of the pump I6. This driving arrangement by the motor 82 serves to drive both the air impelling means and the fluid circulating means.

In addition to the above circulation, there is a circulation of fluid through the line 66 of the line I0. This circulation is in the form of fluid from the heat exchange element I8. It will be recalled that certain of the tubes of the heat exchange element I8 are masked and therefore more or less isolated with respect to the air as it passes through the heat exchange element I8. The reason for this construction is that it reduces the heat exchange action of the heat exchange element I8 to a point below the maximum of which the heat exchange element is capable and, therefore, maintains the temperature of the fluid circulating through the heat exchange element I8 more nearly its original temperature than would be the case if said isolated tubes were not masked. By this construction and arrangement the temperature of the fluid passing from the heat exturn line 53 more nearly approximates the original temperature of the fluid delivered to the return line from the heat exchange element 20. For example, if the fluid be in the form of hot water, the temperature of the water delivered through the line 66 will be higher, due to the masking or isolation of the tubes 30 than would be the case were these tubes subjected to the direct action of the air as it passes through the heat exchange element I8. This feature of the invention is considered an important one since it contributes markedly to the economic and eflicient operation of the apparatus.

By reason of the fact that the air is tempered in the presence of the heat exchange element l8, it enters the air chamber at a temperature different from that at which it enters the heat ex change element l8 and consequently the heat exchange action of the heat exchange elements 40, 42 and 20 is not so great with the result that the temperature of the fluid circulating through these elements does not vary to the same extent as is true of the temperature of the fluid circulating through the heat exchange element 3. For example, when the apparatus is employed as an air heater, air delivered to the air chamber will obviously be of a higher temperature than at the time it enters the heat exchange element l8. This air being of a higher temperature, the load imposed upon the heat exchange elements 40, t2 and 2B is not as great as that imposed upon the heat exchange element l8 and the result is that the temperature of fluid in the line 62 will be higher in the case of heated fluid or lower in the case of cool fluid, than the temperature of the fluid in line 66 and it is to prevent a sudden change of the temperature of this fluid, that certain of the tubes of the heat exchange element are masked to maintain the temperature in the line 66 as near as possible to the initial temperature at which it is supplied to the heat exchange element 88, as heretofore mentioned. Furthermore, it will be obvious that if certain of the tubes of the heat exchange element 20 are also masked, the temperature of the fluid in the line 62 will be maintained even more nearly that at which it is introduced to the heat exchange element I8.

It will also be noted, that the air in its passage through the air chamber and the heat exchange elements l8 and 20 and the fluid in its circulation through the heat exchange elements 40 and 42, move in the same direction and this is an important feature of the invention since the heat exchange action of the heat exchange elements 40 and 42 is not as rapid and consequently the temperature of the fluid circulating therethrough is not changed as rapidly as would be the case if the flow of air and fluid were in counter-directions and the fluid is therefore delivered to the heat exchange element 20 at a temperature more nearly approximating its original temperature than would otherwise be true.

The air in its circulation, passes through the filter It, the heat exchange element l8 Where it is tempered. From the heat exchange element l8 it passes through the air chamber I I where it is thoroughly broken up or agitated by the fan or blower it and where, by reason of the heat exchange elements ll] and 42 in the presence of which the air passes While in the chamber, the air is further tempered. From the chamber the air is discharged through the heat exchange element 2!] and is again further tempered at which point it reaches the temperature to which it is desired to discharge the air into the ducts of an air heating system. It will be understood of course, that by use of suitable well known control devices, not herein shown, any desired operating temperature of delivered air may be had.

It is to'be noted that the air capacity of the heat exchange element I8 is greater than is the air capacity of the heat exchange element 20,

- since the heat exchange element 20 is the smaller change of temperature of the fluid passing through said heat exchange element and by reason of such initial tempering of th air together with the tempering it receives-in its passage through the air chamber II, it may be discharged through the heat exchange element 20 without too greatly eflecting the temperature of the fluid circulating therethrough.

From the foregoing it will be apparent that air in its circulation through the appartus is really subjected to three heating periods and by this method of operation, I have found that the cold spot heretofore mentioned is eliminated and that any reasonable desired temperature of delivered air may be maintained. Furthermore, I have found in actual operation that a desired temperature of delivered air may be maintained constant as distinguished from lags in the air delivery, which lags result in intermittent delivery of heated air as heretofore mentioned as present in apparatus of this type as generally constructed and operated.

The apparatus has been described throughout as air heating apparatus. however, that it is not limited to the heating of air alone, but, as proven, is equally eflicient in the cooling of air.

Cold water is supplied from a l ne I00 which is connected as at I02 to the line 59 which, it will i be remembered, is the fluid supply line of the heat exchange element I8, and this line I08 may be controlled by a small valve I04. When the apparatus is thus employed the several heat exchange elements function to maintain a rela tively low degree of temperature of the circulating air as distinguished from the relatively higher temperature when the apparatus is operating as an air heating 'means. i

A valve 59' cuts off the heater 56 and permits of a direct pull upon the line Why the pump 16. The pump maintains the circulation and delivers fluid to the line 53 which is cut off from the heater by a valve 53'. A return or discharge pipe 50' controlled by a valve 54 and connected to the line 53 at 52, completes the circulation of fluid through the apparatus.

In connection with the apparatus, I have devised a special form of fluid heating element and I will now describe its construction. In the device as illustrated in Figures 5 through 8 of the drawings andit comprises a shell or housing N0,

It is to be understood,

to a fitting H6 and-extending from said fitting there are four coils H8 arranged in such a man. s

within the coils will be delivered to the water space N4 of the dome 58 from which it is delivered to the supply line 59 heretofore mentioned.

By reference to Figure 8 it will be noted that the interior of thedome or the inner wall of the water space H4 is provided with a plurality of heat radiating fins I30. These fins perform two purposes in that they both retard or prevent, to a decided extent, a swirling of the flame and gases within the dome 58 and also serve to transmit heat to the inner wall of said dome to increase the heat transfer efliciency thereof.

The shell I I0 is provided with a flue connection I32 and partially masking the flue connection I32 there is a bafile I34 which, as illustrated in Figures 6 and 8, is of segmental form and of such size as to extend over a portion, at least, of that coil H8 Which rises directly in line with the flue opening I32.

While in the present illustration of the invention, hot water has been described as the heating medium, it will be obvious that steam, vapor or other suitable heating medium may be employed if desired.

By the above construction and arrangement of parts I have found that a water heater of high efliciency is obtained and which will adequately meet the demands of the apparatus herein set forth.

Having thus described the invention what is claimed as new is:

1. In apparatus for conditioning air, an air chamber, said air chamber having an air inlet and an air outlet, a heat exchange element in the air inlet, a heat exchange element in the air outlet and air impelling means for drawing air into the chamber in the presence of the heat exchange element associated therewith and discharging it from the outlet in the presence of the heat exchange element associated therewith, the air inlet and its associated heat exchange element being of greater capacity in comparison to the capacity of the air outlet and its associated heat exchange element whereby the air will be passed through the air outlet at a velocity greater than the velocity at which the air passes through the air inlet.

2. Apparatus for heating air comprising in combination, a housing having an air inlet and an air outlet, a heat exchange element of the fluid heated type in the presence of which the air enters said housing, a second heat exchange element of the fluid heated type in the presence of which the air passes as it is discharged from the housing, means for connecting together said heat exchange elements whereby heated fluid supplied to the first mentioned heat exchange element will be conveyed to the second mentioned heat exchange element, means for circulating air through said housing and in the presence of said heat exchange elements, a fluid heating device and a fluid circulating system connecting the fluid heating device with each of said heat exchange elements, said fluid circulating system including a fluid supply line leading from said fluid heating element to the first mentioned heat exchange element, a fluid return line connecting the second mentioned heat exchange element with the fluid heating element, and a line for introducing fluid to the fluid return line at a higher degree of temperature than the temperature of fluid in the fluid return line.

3. Apparatus for heating air comprising in combination, a housing having an air inlet and an air outlet, a heat exchange element of the fluid heated type in the presence of which the air enters said housing, va second heat exchange element of the fluid heated type in the presence of which the air passes as it is discharged from the housing, means for connecting together said heat exchang elements whereby heated fluid supplied to the first mentioned heat exchange element will be conveyed to the second mentioned heat exchange element, means for circu-- lating air through said housing and in the presence of said heat exchange elements, a fluid heating device and a fluid circulating system connecting the fluid heating device with each of said heat exchange elements, said fluid circulating system including a fluid supply line leading from said fluid heating element to the first mentioned heat exchange element, a return fluid line connecting the second mentioned heat exchange element with the fluid heating element, and a line leading from the first mentioned heat exchange element to th fluid return line for introducing thereto, fluid at a temperature higher than the temperature of fluid in the return line.

JOHN E. SCHARFF. 

